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authorEric Dumazet <edumazet@google.com>2022-02-10 13:42:31 -0800
committerDavid S. Miller <davem@davemloft.net>2022-02-11 11:44:27 +0000
commit29e5375d7fcb5f88b438d74d537bbfd67ac75a64 (patch)
tree5c85b956925de91067e6cef0af62465f4aa26443 /net/ipv4/route.c
parentba55ef81637c61e52772bcd4e5fba10ec7190d2a (diff)
ipv4: add (struct uncached_list)->quarantine list
This is an optimization to keep the per-cpu lists as short as possible: Whenever rt_flush_dev() changes one rtable dst.dev matching the disappearing device, it can can transfer the object to a quarantine list, waiting for a final rt_del_uncached_list(). Signed-off-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv4/route.c')
-rw-r--r--net/ipv4/route.c12
1 files changed, 9 insertions, 3 deletions
diff --git a/net/ipv4/route.c b/net/ipv4/route.c
index 634766e6c7cc..202d6b1fff43 100644
--- a/net/ipv4/route.c
+++ b/net/ipv4/route.c
@@ -1485,6 +1485,7 @@ static bool rt_cache_route(struct fib_nh_common *nhc, struct rtable *rt)
struct uncached_list {
spinlock_t lock;
struct list_head head;
+ struct list_head quarantine;
};
static DEFINE_PER_CPU_ALIGNED(struct uncached_list, rt_uncached_list);
@@ -1506,7 +1507,7 @@ void rt_del_uncached_list(struct rtable *rt)
struct uncached_list *ul = rt->rt_uncached_list;
spin_lock_bh(&ul->lock);
- list_del(&rt->rt_uncached);
+ list_del_init(&rt->rt_uncached);
spin_unlock_bh(&ul->lock);
}
}
@@ -1521,20 +1522,24 @@ static void ipv4_dst_destroy(struct dst_entry *dst)
void rt_flush_dev(struct net_device *dev)
{
- struct rtable *rt;
+ struct rtable *rt, *safe;
int cpu;
for_each_possible_cpu(cpu) {
struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
+ if (list_empty(&ul->head))
+ continue;
+
spin_lock_bh(&ul->lock);
- list_for_each_entry(rt, &ul->head, rt_uncached) {
+ list_for_each_entry_safe(rt, safe, &ul->head, rt_uncached) {
if (rt->dst.dev != dev)
continue;
rt->dst.dev = blackhole_netdev;
dev_replace_track(dev, blackhole_netdev,
&rt->dst.dev_tracker,
GFP_ATOMIC);
+ list_move(&rt->rt_uncached, &ul->quarantine);
}
spin_unlock_bh(&ul->lock);
}
@@ -3706,6 +3711,7 @@ int __init ip_rt_init(void)
struct uncached_list *ul = &per_cpu(rt_uncached_list, cpu);
INIT_LIST_HEAD(&ul->head);
+ INIT_LIST_HEAD(&ul->quarantine);
spin_lock_init(&ul->lock);
}
#ifdef CONFIG_IP_ROUTE_CLASSID